The CDI tells you which heading to turn to if you dial in the correct OBS.
Which do you think is more useful command: turn left, or turn to a heading
of xxx?

If I'm already pointing more or less in the right direction, "turn
left" is more useful. If not, the actual heading is.

When on an approach, I'm pointing more or less in the direction I want
to go, and I use the CDI to make small corrections to keep on the
flight path I want. So long as these corrections remain small, and I
remain more or less on the localizer, all I need is "a little more
left". The command "turn to heading xxx" requires me to figure out
how to get to xxx. "turn a little left" does not.

Jose
--
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